Costa Rican Octopus?????

I was at my lfs this evening and they had a very interesting octo! It was labeled a "Costa Rican Octopus", which I assumed was something like an O. Vulgaris. Upon closer inspection, what he really looked like was a much bigger version of O. Aculeatus....but with larger eyes. I've tried to research this species, but have had little to no luck. His resting color is a pale green/yellow, although he does turn black and white/stripey like my aculeatus when stimulated or irritated.
His mantle is oval and smooth in shape, with large, round eyes. The texture of his skin when agitated has identical fronds mimicking algae [including the telltale ones above each eye], like that of an aculeatus. In any ordinary circumstance, I would have passed it off as an aculeatus....however....this guy is waaaaay too big. His mantle is about the size of a closed adult human fist. I've posted a photo below. Sorry for the quality, all I had on me was my cell phone. Anyone have any ideas??

Just wondering. Where did you see this Costa Rican Octopus?
Was it at a local fish store in Hayward Ca?

If so I saw this one too.

Mike

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yup yup, same one. they actually have two there, i think...at least they did the last time i went in there. One is smaller, a little more purple....same origin. It's a great aquarium store and they are really knowledgeable, but they don't know a thing about octopi....so if you're lookin for answers, I wouldn't ask there.